UNIVERSITY    OF   CALIFORNIA 

COLLEGE    OF    AGRICULTURE 

AGRICULTURAL   EXPERIMENT  STATION 

CIRCULAR  No.  263 


TOMATO  PRODUCTION  IN  CALIFORNIA 

By  J.  T.  EOSA 


The  production  of  tomatoes  is  one  of  the  important  agricultural 
industries  of  California.  In  1922,  2,226  carloads  of  tomatoes  were 
shipped  for  table  purposes;  the  canneries  packed  1,925,389  cases  of 
the  whole  tomato,  and  1,498,617  cases  of  other  tomato  products,  such 
as  pulp,  puree,  catsup,  and  paste.  Large  quantities  are  grown  for 
local  markets;  a  considerable  acreage  is  grown  especially  for  seed 
production;  and  in  home  gardens  throughout  the  state  the  tomato  is 
a  crop  of  first  importance.  Thus  it  is  seen  that  the  tomato  is  grown 
for  a  number  of  distinct  purposes  in  the  state,  each  amounting  to 
a  business  of  considerable  proportions.  While  each  of  these  lines 
of  production  and  utilization  have  grown  steadily  in  recent  years, 
there  is  at  the  present  time  some  concern  over  the  relatively  low  yield 
per  acre.  The  average  yield  for  California  has  varied  from  5.5  to 
7.2  tons  an  acre  in  recent  years.  "While  these  yields  are  much  above 
the  average  for  the  whole  United  States,  they  are  far  below  the  possi- 
bilities of  economic  production  with  the  favorable  soil  and  climatic 
conditions  existing  in  many  sections  of  the  state.  Yields  of  ten  to 
twenty-five  tons  per  acre  are  frequently  obtained  and  such  yields 
are  attainable  easily  by  skillful  growers.  Surveys  in  other  states 
have  shown  that  the  grower  producing  yields  below  the  average  is 
likely  to  be  losing  money  on  the  crop,  while  other  growers  in  the 
same  district  whose  yields  are  above  the  average,  make  a  good  profit. 
The  object  of  this  circular  is  to  describe  successful  methods  of  grow- 
ing and  handling  the  crop,  and  to  point  out  in  a  general  way  some 
of  the  basic  principles  underlying  better  production.  However, 
when  the  culture  of  such  a  crop  as  tomatoes  is  considered,  due  allow- 
ance must  always  be  made  for  the  diversity  in  soil  and  climatic 
conditions  existing  within  the  state,  and  the  variety  of  purposes  for 
which  the  crop  is  grown. 


Z  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

PKODUCING  EEGIONS 

At  present  commercial  production  is  more  or  less  centered  in  a 
number  of  important  districts.  The  earliest  tomatoes  are  grown  in 
the  Imperial  Valley  and  are  shipped  in  considerable  quantities  to 
Western  markets.  Possibly  the  use  of  a  better  shipping  variety, 
or  the  adoption  of  better  cultural  practices,  may  result  in  the  pro- 
duction of  fruit  that  can  be  marketed  successfully  further  east  in 
competition  with  the  Florida  crop.  • 

Los  Angeles,  Ventura,  Riverside,  Orange  and  San  Diego  counties 
produce  a  large  quantity  of  tomatoes  for  all  of  the  uses  to  which  the 
crop  is  put,  but  most  important  part  of  the  tomato  business  in  this 
district  is  the  production  of  a  late  or  fall  crop  for  eastern  shipment. 
From  September  to  December,  after  disease  has  killed  the  plants 
in  the  southern  states  and  frost  has  ended  the  crop  in  the  northern 
states,  there  is  a  good  demand  for  California  tomatoes  in  the  East. 

The  San  Joaquin  Valley  has  considerable  tomato  production, 
most  important  being  the  production  of  early  tomatoes  for  shipment, 
centered  at  Merced.  After  the  shipping  season  ends,  the  later  part 
of  the  crop  is  utilized  for  manufacturing  purposes.  Tomato  pro- 
duction in  this  section  is  on  an  extremely  intensive  basis  and  the 
returns  by  the  acre  are  high. 

The  Santa  Clara  Valley  is  one  of  the  oldest  and  most  important 
districts  for  the  production  of  tomatoes  for  canning  and  manu- 
facturing. 

The  San  Francisco  Bay  district  is  an  important  producer  of  can- 
ning and  manufacturing  stock,  as  well  as  fruit  for  local  markets  and 
for  shipment  to  the  East  during  the  fall  months.  Some  growers 
contract  their  entire  crop  to  a  cannery,  while  others  ship  their  crop 
when  market  conditions  provide  a  profitable  outlet,  but  when  the 
market  demand  is  not  good,  turn  their  crop  or  a  portion  of  it  to 
the  canneries. 

The  Sacramento  Valley  has  several  districts  which  are  producing 
canning  tomatoes  extensively.  One  of  the  most  important  districts 
is  around  Sacramento. 

Sonoma  County  is  one  of  the  most  important  districts  for  can- 
nery production. 

There  are  many  other  localities  where  the  crop  is  grown  for  can- 
ning and  other  purposes  on  a  smaller  scale.  Production  for  local 
markets  is  more  or  less  important  in  all  parts  of  the  state.  Fifty- 
two  counties  in  California  report  a  commercial  tomato  acreage.  The 
most  important  counties  in  point  of  production  are  listed  in  the  fol- 
lowing table  with  the  number  of  acres  for  1919. 


Circular  263] 


TOMATO  PRODUCTION   IN    CALIFORNIA 


CALIFORNIA  TOMATO  ACREAGE   BY   COUNTIES 


ACRES 

Alameda 3,609 

Contra  Costa  834 

Imperial  270 

Kern  144 

Los  Angeles 8,021 

Monterey  105 

Orange   1,331 

Riverside  1,109 

Sacramento  1,005 

San  Benito  819 


ACRES 

San  Bernardino  710 

San  Diego  609 

San  Joaquin  1,480 

San  Mateo 308 

Santa  Clara 5,679 

Solano  529 

Sonoma  1,708 

Stanislaus   986 

Ventura 128 

Yolo    1,439 


Fig.  1. — Showing  the  total  carload  shipments  of  tomatoes  for  the  United 
States  by  weeks  in  1921  and  1922. 


UNIVERSITY   OF    CALIFORNIA — EXPERIMENT    STATION 


SHIPMENT  SEASONS 


To  make  clearer  the  opportunities  for  tomato  production  for  ship- 
ment to  outside  markets,  and  to  show  the  relation  of  tomato  shipments 
from  California  to  those  from  other  sections  and  from  the  United 
States  as  a  whole,  two  shipment  charts  have  been  prepared. 


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Fig.  2. — Showing  the  volume  and  season  of  shipment  of  tomatoes  from  the 
principal  districts. 


CIRCULAR  263]  TOMATO  PRODUCTION   IN   CALIFORNIA  5 

A  glance  at  figure  1  shows  that  tomatoes  are  shipped  almost 
throughout  the  year.  Shipments  gradually  increase  during  the  early 
spring  until  a  peak  is  reached  in  June.  Thereafter,  shipments  de- 
crease and  the  total  number  of  cars  shipped  during  July  and  August 
is  relatively  low.  This  is  the  period  of  local  production  in  the  North 
and  East,  so  that  carload  shipments  from  outside  districts  are  not 
needed.  Late  in  August,  shipments  begin  to  increase  considerably, 
and  the  market  on  tomatoes  improves  at  this  season  due  to  exhaus- 
tion of  home-grown  supplies  in  the  East.  This  leads  to  a  second 
peak  of  shipments  during  the  fall,  which  declines  rapidly  as  frost 
cuts  down  one  shipping  section  after  another.  By  the  middle  of 
December  the  only  shipments  of  any  importance  are  those  from 
Mexico.  It  is  noted  in  figure  2  that  shipments  of  early  tomatoes 
in  California  are  not  very  important,  due  to  heavy  production  in 
other  sections  nearer  the  big  markets  of  the  country.  However, 
after  the  first  week  of  October,  California  is  the  only  important 
shipper  of  tomatoes.  For  a  period  of  two  months  in  the  fall,  Calif- 
ornia tomatoes  have  command  of  the  markets  of  the  entire  country. 
Production  for  shipment  in  this  period  seems  especially  promising. 

LOCATIONS  FOE  TOMATO  PEODUCTION 

Before  engaging  in  extensive  tomato  production,  the  grower  must 
make  sure  that  there  is  a  profitable  outlet  for  his  crop,  that  is,  he 
must  have  access  to  a  good  local  market,  to  a  cannery  or  other  manu- 
facturing plant,  or  be  so  situated  that  he  can  ship  to  advantage. 
It  is  not  advisable  to  grow  the  crop  for  shipment  unless  the  acreage 
is  large  enough  to  make  carload  lots  possible,  either  by  the  individual 
grower  or  by  groups  or  associations  of  smaller  growers  located  in 
the  same  community.  There  are  several  such  associations  doing  a 
successful  business  in  the  state,  and  there  should  be  more  of  them. 
The  season  at  which  the  crop  will  mature  and  the  probable  market 
conditions  existing  at  that  season  should  also  be  considered. 

Cultural  conditions  must  also  receive  attention.  The  tomato  is 
a  heat-loving  plant  and  the  long  growing  season  in  most  parts  of 
the  state  is  very  favorable  for  tomato  production.  Localities  subject 
to  late  spring  or  early  fall  frosts,  or  with  very  cool  summer  climate 
are  not  suitable  for  the  crop.  As  to  soil,  the  tomato  is  not  particular, 
though  this  factor  influences  yield,  quality  and  time  of  maturity 
to  some  extent.  Muck  soils  produce  a  very  poor  quality  of  fruit,  sandy 
soils  favor  an  early  maturing  crop,  while  heavier  soils  are  especially 
suited  for  late  maturing  or  fall  crops.     Good  drainage  is  always 


b  UNIVERSITY   OF    CALIFORNIA — EXPERIMENT   STATION 

essential.  Soils  that  are  too  moist  for  any  considerable  period  during 
the  growing  season  usually  produce  a  poor  crop.  Tomatoes  in  some 
sections  are  grown  on  sub-irrigated  land.  If  the  water-table  comes 
too  near  the  surface,  excessive  vine  growth  and  a  poor  set  of  fruit 
will  result.  Soils  that  are  excessively  rich  in  nitrogenous  matter 
may  produce  the  same  bad  result. 

CROPPING  SYSTEMS 

At  present  a  large  portion  of  the  tomato  crop  in  northern  and 
central  California  is  produced  in  connection  with  a  winter  crop  of 
spinach.  The  tomato  vines  are  pulled  and  burned  at  the  end  of  the 
season  in  November,  the  land  is  fitted  and  sown  to  spinach  at  once. 
The  spinach  crop  is  harvested  in  March  and  April,  and  the  land 
fitted  in  time  to  plant  tomatoes  again.  This  combination  is  a  good 
one,  but  will  lead  to  bad  results  if  the  same  land  is  continuously 
cropped  in  this  way,  in  fact,  it  seems  that  this  practice  is  partly 
responsible  in  some  cases  for  recent  low  yields  of  tomatoes.  Tomatoes 
should  not  be  grown  more  than  once  in  four  years  on  the  same  piece 
of  land;  they  should  be  grown  in  rotation  with  other  crops.  Vari- 
ous diseases  often  become  very  common  and  do  much  damage  when 
tomatoes  are  grown  continuously. 

Tomatoes  are  extensively  grown  as  an  intercrop  in  young  orchards, 
to  which  purpose  they  are  well  adapted  when  the  irrigation  practice 
for  tomatoes  does  not  conflict  with  the  requirements  of  the  trees. 
This  may  sometimes  be  an  objection,  especially  in  young  walnut 
groves. 

PLANT  PRODUCTION 

For  the  sake  of  economy  of  seed,  earliness  and  convenience  in 
growing  the  crop,  the  plants  are  usually  grown  in  beds  of  one  kind 
or  another,  from  which  the  plants  are  transplanted  to  the  field  at 
the  proper  time.  The  best  method  of  growing  the  plants  varies 
according  to  the  locality  and  the  season  at  which  the  crop  is  desired. 

The  Hotbed-Coldframe  Method. — The  hotbed-coldframe  method  is 
generally  best  for  early  market  crops,  and  perhaps  should  be  used  even 
for  the  late  shipping  and  canning  crop  in  central  and  northern  Calif- 
ornia. This  method  is  described  in  detail  herein,  because  its  more 
extensive  use  seems  desirable.  The  hotbed  frame  should  be  located  in 
a  warm,  sunny,  well  drained  spot.  About  one  foot  of  fresh  hot  horse 
manure  is  placed  in  the  bed,  tramped  down,  and  a  layer  of  soil  four 


Circular  263]  TOMATO  PRODUCTION   IN   CALIFORNIA  7 

inches  deep  placed  over  this.  It  is  best  to  use  a  sandy  soil  or  a  mixture 
of  one-half  sand  and  one-half  garden  soil  in  the  hotbed.  This  gives 
stronger  plants  with  good  root  systems.  The  seeds  are  planted  about 
ten  weeks  before  time  of  field  setting,  sowing  them  broadcast,  or 
drilled  into  rows  about  four  inches  apart  and  covered  about  one- 
half  inch  deep.  If  good  seed  are  sowed  at  the  rate  of  twelve  or 
fifteen  seeds  per  inch  of  row,  one  hotbed  six  by  twenty-four  feet  in 
size  should  produce  about  50,000  seedlings.  The  hotbed  should  be 
kept  warm  and  moist  until  the  plants  are  up,  after  which  time  it 
should  be  well  ventilated  and  watered  sparingly.  As  soon  as  the 
seedlings  show  their  first  rough  leaves,  they  are  ready  to  transplant 
to  the  coldframe.  This  is  a  tedious  task  but  one  that  is  worth  doing 
well  and  carefully.  The  coldframes  are  prepared  much  like  the 
hotbeds  except  that  no  manure  is  placed  under  them.  A  suitable 
covering  for  the  frames  may  be  made  of  eight  or  ten-ounce  muslin. 
About  four  inches  of  fine  soil  should  be  placed  in  the  coldframe, 
preferably  a  mixture  of  one  part  garden  soil,  one  part  sand,  and 
one  part  rotted  manure,  all  well  mixed  and  screened  through  a  screen 
of  one-half-inch  mesh  if  possible.  The  seedling  plants  from  the 
hotbed  are  set  therein  about  two  by  two  inches  apart  usually,  though 
wider  spacing  will  give  better  results.  Watering  should  follow  trans- 
planting and  the  frames  should  be  kept  covered  a  few  days,  until 
the  plants  have  taken  root.  This  is  especially  necessary  if  the  sun 
is  warm  or  the  weather  windy.  After  the  plants  have  begun  to  grow, 
the  frames  should  be  ventilated  freely  during  the  day  time,  and 
watered  only  enough  to  keep  the  plants  growing  fairly  fast.  When 
the  plants  are  ten  inches  high,  the  beds  should  be  gone  over  and 
the  terminal  bud  pinched  out  of  each  plant.  This  prevents  the 
plants  from  growing  any  taller,  and  encourages  the  development  of 
thick  stout  stems  and  good  root  systems.  At  the  same  time,  shoots 
begin  to  develop  in  the  axils  of  the  leaves.  In  this  manner,  the  frame- 
work for  a  large  bushy  plant  is  started  before  the  plants  are  set  in  the 
field.  This  treatment  of  "topping"  the  plants  two  or  three  weeks 
before  transplanting  to  the  field  has  been  found,  in  experiments  by 
the  writer,  to  result  in  considerable  increases  in  yield  of  fruit.  It 
has  also  been  successfully  practiced  for  years  by  certain  growers  in 
the  Sacramento  district,  and  perhaps  elsewhere. 

For  a  week  or  ten  days  before  transplanting  the  plants  to  the 
field,  the  beds  should  be  left  open  day  and  night,  and  only  enough 
water  applied  to  keep  the  plants  from  very  serious  wilting.  This 
treatment  toughens  or  "hardens"  the  plants  so  that  they  will  stand 
transplanting  without  damage  or  severe  shock,  which  so  often  kills 
tender  plants  when  set  in  the  open  field. 


8  UNIVERSITY    OF    CALIFORNIA — EXPERIMENT    STATION 

The  Coldframe  Method. — This  method  is  frequently  used  where 
plants  have  to  be  started  during  cool  weather  but  not  so  early,  as 
to  require  the  hotbed  method.  Frames  are  prepared  running  east 
and  west  in  a  sheltered  sunny  spot.  A  four-inch  layer  of  sandy, 
fertile  soil  should  be  placed  in  the  frame.  The  seed  are  sowed  by 
hand  or  with  a  seed  drill,  being  planted  thinly  in  rows  four  to  six 
inches  apart.  After  germination,  the  beds  should  be  weeded  and  the 
plants  thinned  to  about  three  plants  per  inch.  This  method  can  be 
used  to  produce  large  numbers  of  plants  cheaply,  but  good  large 
stocky  plants  with  well-developed  roots  are  seldom  grown  in  this 
way,  the  seed  being  usually  planted  too  thick  and  the  growers  fail- 
ing to  do  the  necessary  thinning. 

The  Open  Bed  Method. — This  is  probably  the  cheapest  way  to 
grow  plants  but  it  is  not  adapted  for  sections  having  short  growing 
seasons  or  for  early  crop  production.  It  is  adapted  for  growing 
plants  for  the  late  shipping  crop  in  southern  California  and  for  the 
canning  crop  in  northern  California,  though  in  the  latter  case  it  is 
believed  that  the  hotbed  method  is  really  better.  For  the  open  bed 
method,  beds  are  prepared  in  a  well  drained  sheltered  spot,  prefer- 
ably where  the  soil  is  sandy.  The  seed  are  drilled  in  with  a  seeder 
as  soon  as  the  soil  warms  up  and  danger  of  frost  is  over  (about 
March  15  in  the  Sacramento  district).  Narrow  beds  thirty  to  thirty- 
six  inches  from  center  to  center  are  thrown  up  with  a  lister,  the 
ridges  are  harrowed  down  and  levelled  with  a  planker,  and  a  double 
row  is  sowed  on  each  bed.  The  furrow  between  the  beds  is  used  for 
irrigation  when  necessary.  It  is  very  important  to  see  that  the  seed 
are  not  planted  too  thickly  even  in  these  open  beds,  and  thinning 
the  plants  in  the  thicker  portions  of  the  bed  should  be  practiced. 

Care  of  Plant  Beds. — Plant  beds  must  be  weeded  and  cultivated  to 
prevent  crust  formation  around  the  plants.  Thinning  the  plants 
is  often  necessary,  for  if  crowded  they  develop  weak  spindling  stems 
resulting  in  plants  of  very  poor  quality.  Particular  care  should  be 
given  to  the  watering  of  plant  beds,  for  over-watering  results  in  weak, 
sappy,  leggy  plants  that  are  hard  to  transplant  to  the  field  and  which 
recover  slowly  if  they  survive  transplanting.  Excessive  moisture, 
especially  if  given  late  in  the  day,  encourages  "damping  off,''  a 
disease  which  sometimes  wipes  out  many  plants  overnight.  Water- 
ings should  be  given  usually  several  days  apart,  and  not  until  the 
plants  show  need  for  it.  No  harm  is  done  if  the  plants  are  checked 
by  lack  of  water.  Tomatoes,  unlike  most  other  vegetable  plants, 
suffer  little  permanent  injury  even  if  severely  checked  in  the  seed- 


CIRCULAR  263]  TOMATO  PRODUCTION   IN   CALIFORNIA  9 

ling  stage.  However,  holding  plants  for  a  long  period  after  they 
have  reached  transplanting  size  will  lead  to  bad  results. 

The  day  before  transplanting  to  the  field,  the  beds  should  be 
soaked  well  so  that  the  plants  can  be  easily  removed.  In  taking 
up  the  plants,  it  is  better  to  dig  them  with  a  spade,  rather  than  to 
pull  out  by  hand,  which  is  the  too  general  practice. 

Seeding  directly  in  the  field. — In  sections  having  a  long  season, 
tomatoes  may  and  sometimes  are,  planted  directly  in  the  field  when 
the  soil  has  become  warm.  This  method  is  wasteful  of  seed,  involves 
considerable  labor  in  thinning,  and  is  seldom  practiced  when  tomatoes 
follow  a  spring  crop  of  spinach.  Only  varieties  that  mature  in  a 
medium  or  short  season  should  be  grown  this  way. 

FIELD  CULTURE 

Except  where  following  spinach  or  other  winter  crop,  tomato  land 
should  be  fall-plowed  as  deeply  as  possible.  In  spring,  before  the 
surface  gets  hard  and  dry,  the  land  should  be  disced  to  kill  weeds 
and  get  the  soil  into  fine  condition.  The  method  of  preparing  for 
the  plants  and  method  of  transplanting  depends  upon  the  locality 
and  the  soil  conditions.  In  most  sections,  when  setting  for  the  early 
crop,  it  is  easy  to  set  the  plants  without  watering  if  the  soil  is  handled 
properly.  Under  such  conditions,  the  field  is  prepared  level  and 
marked  off  in  both  directions  and  the  plants  set  at  the  intersections 
if  they  are  set  by  hand.  In  setting  large  acreages,  however,  much 
time  and  labor  can  be  saved  by  the  use  of  a  horse-drawn  transplanter. 
These  machines,  of  which  there  are  several  types  on  the  market, 
set  the  plants  as  well  as  they  are  usually  set  by  hand,  and  can  be  used 
to  water  the  plants  if  watering  is  necessary. 

In  dry  sections  and  in  most  sections  during  dry  seasons,  it  is 
necessary  to  water  the  plants  as  they  are  transplanted.  This  is 
almost  always  necessary  in  setting  the  late  crop.  If  irrigation  water  is 
available,  the  simplest  plan  is  to  mark  the  rows  with  a  plow.  The 
plants  are  set  the  proper  distance  apart  on  the  edge  of  the  furrow 
and  a  small  stream  of  irrigation  water  is  turned  into  each  row  as 
it  is  set.  Cultivation  must  follow  within  a  day  or  two,  to  prevent 
a  hard  crust  forming  around  the  roots.  At  this  time  the  soil  should 
be  worked  toward  the  plants,  thus  beginning  the  bed  which  should 
be  gradually  formed  for  each  row. 

Another  way  to  set  plants  under  dry  conditions  is  to  haul  a 
number  of  barrels  of  water  into  the  field,  placing  the  barrels  across 
the  field  at  convenient  intervals.  As  the  plants  are  set,  a  little  water 
is  poured  about  the  roots  from  a  can. 


10  UNIVERSITY    OF    CALIFORNIA — EXPERIMENT    STATION 

In  transplanting  tomatoes,  the  plants  should  be  set  as  deeply  as 
possible,  usually  four  or  five  inches  deeper  than  the  plants  were  in 
the  plant  bed.  New  roots  develop  along  the  stem  giving  the  plant 
a  much  larger  and  deeper  root  system  than  can  be  obtained  when 
the  plants  are  small  and  set  shallow.  Deep  setting  is  of  course  more 
laborious  than  the  customary  shallow  setting,  but  it  encourages  the 
plants  to  develop  large,  deep  root  systems,  which  enables  plants  to 
make  use  of  the  moisture  in  the  lower  soil.  Deeper  plowing  than 
usual  for  tomatoes  aids  in  securing  the  same  result.  Plants  with 
deep  roots  are  most  assured  of  an  even  moisture  supply,  do  not 
require  so  frequent  irrigations,  and  do  not  suffer  from  the  sharp 
fluctuations  of  alternately  having  too  much  and  not  enough  water. 
It  seems  that  many  of  the  troubles  affecting  tomato  plants  in  Calif- 
ornia are  connected  with  their  shallow  root  systems. 


BHRPI 

m                HHhN 

r ; ^fe*                     ■  ***^J???!Z.  _ 

Fig.  3. — A  tomato  field  furrowed  for  irrigation. 

Irrigation. — In  some  parts  of  the  state,  satisfactory  tomato  crops 
can  be  grown  with  little  or  no  irrigation,  if  the  plants  are  given  a 
chance  to  develop  deep  root  systems.  However,  in  most  sections 
some  irrigation  is  necessary,  the  number  and  frequency  of  irrigations 
being  determined  mostly  by  local  conditions.  Enough  water  should 
be  applied  to  keep  the  plants  growing  steadily.  Over-irrigation 
favors  excessive  vine  growth  and  sometimes  causes  the  blossoms  to 
drop  without  setting  fruit.  The  best  method  is  to  open  a  furrow 
alongside  each  row  of  plants  so  that  the  moisture  can  seep  down  to 
the  roots  without  wetting  or  compacting  the  surface  soil  (fig.  3). 
Cultivation  should  follow  promptly,  throwing  the  soil  toward  the 
plants.  For  each  successive  irrigation,  the  furrow  is  made  further 
from  the  plants  and  by  mid-season  a  broad  low  bed  has  been  formed, 
which  is  covered  by  the  sprawling  plants.  Between  the  beds  is  the 
dead-furrow  which  may  be  used  for  later  irrigations,  allowing  the 
water  to  seep  down  to  the  roots  without  wetting  the  surface  on  which 
vines  and  fruit  are  resting. 


CIRCULAR  263]  TOMATO  PRODUCTION   IN    CALIFORNIA  11 

There  are  two  periods  at  which  water  should  not  be  applied — 
during  the  period  when  the  first  blossoms  are  open,  and  during 
the  latter  part  of  the  fruit-ripening  period.  Irrigation  at  the  earlier 
period  will  decrease  the  set  of  fruit,  and  at  the  later  period  will 
retard  the  maturing  of  the  crop.  However,  in  some  sections  where  a 
late  crop  is  grown  for  fall  shipment,  the  practice  is  to  irrigate  just 
as  the  first  cluster  begins  to  bloom.  This  prevents  the  setting  of  early 
fruit  and  may  encourage  the  development  of  a  larger  plant  that  will 
produce  more  late  fruit. 

Planting  distances. — The  planting  distance  is  determined  by  the 
variety,  the  soil,  and  the  season  at  which  the  crop  is  grown.  Early 
tomatoes  grown  under  intensive  culture,  where  the  plants  are  staked 
and  trained  to  a  single  stem,  as  in  the  Merced  district,  are  set  15 
inches  by  3  feet  apart,  this  requiring  about  12,000  plants  per  acre. 
Early  varieties  where  not  staked  and  pruned,  are  usually  set  about 
three  by  four  feet,  requiring  about  3,600  plants  per  acre.  The  late 
shipping  and  canning  crop,  the  varieties  used  for  which  generally 
make  very  vigorous  vine  growth,  are  set  from  6  by  6  feet  to  8  by  8 
feet  apart,  depending  on  the  locality  and  soil  fertility.  This  crop 
then  requires  from  700  to  1,200  plants  per  acre. 

The  wider  spacings  are  more  economical  of  plants  and  labor  than 
the  closer  plantings.  Yet  there  is  no  reliable  data  available  to 
indicate  whether  wide  or  close  planting  pays  best.  Certainly  the 
rows  must  be  wide  enough  to  allow  cultivation  and  irrigation  and 
to  permit  easy  passage  for  the  pickers  without  trampling  upon  the 
plants. 

HARVESTING 

The  exact  stage  of  maturity  at  which  the  fruit  is  picked  depends 
upon  the  purpose  for  which  it  is  to  be  used. 

For  sale  on  local  markets,  for  canning  and  for  pulp  manufacture, 
the  fruit  should  be  well  colored  when  picked. 

For  shipment  to  nearby  points  the  fruit  is  harvested  in  the  ' '  pink ' ' 
stage,  when  about  half  of  the  surface  shows  distinct  color. 

For  shipment  to  distant  markets,  the  fruit  is  picked  usually  in 
the  "green-mature"  stage — when  fully  grown  but  not  yet  begin- 
ning to  show  color.  Fruit  at  this  stage  should,  however,  appear 
whitish  at  the  blossom  end.  Mature  green  fruits  if  cut  open  are 
found  to  have  the  cells  well  filled  with  the  gelatinous  pulp  in  which 
the  seeds  are  embedded.  Fruits  picked  in  the  green-mature  stage 
ripen  and  color  up  perfectly  in  from  one  to  three  weeks,  depending 
upon   the   temperature.     The   quality   of   such   fruit   is   good   when 


12  UNIVERSITY    OF    CALIFORNIA — EXPERIMENT    STATION 

ripened  in  air,  but  when  wrapped  in  tissue  paper,  as  is  the  usual 
commercial  practice,  the  flavor  and  texture  of  the  artificially  ripened 
fruit  is  not  so  good.  Another  defect  in  the  practice  of  picking  and 
shipping  green-mature  fruit  is  that  careless  pickers  gather  many 
fruits  that  are  not  mature.  Such  fruits  are  worse  than  a  dead  loss 
to  the  grower,  for  they  never  attain  good  edible  quality  when  arti- 
ficially ripened. 

For  shipping  tomatoes,  the  fields  are  generally  gone  over  once 
a  week,  and  fruit  in  all  of  the  above  stages  of  ripeness  gathered  at 
once.  The  ripe  fruits,  however,  are  placed  in  separate  containers 
by  the  picker,  and  are  disposed  of  on  the  local  market  or  to  the 
canner.  The  pink,  turning,  and  green  fruit  is  hauled  to  the  packing 
shed,  where  it  is  sorted,  graded,  wrapped  and  packed  for  shipment. 
This  part  of  handling  the  crop  can  generally  be  taken  care  of  through 
a  local  cooperative  packing  and  shipping  association,  or  by  a  reput- 
able distributing  organization,  better  than  by  the  individual  grower. 

Great  care  should  always  be  taken  in  handling  tomatoes  for  any 
or  all  purposes,  to  avoid  bruising  or  breaking  the  skin.  The  tomato 
fruit  is  a  highly  perishable  article  at  best.  Pickers  should  always 
remove  the  stems  from  the  fruits  as  they  are  picked,  to  prevent 
puncturing  the  skins  of  other  fruits. 

Persons  interested  in  the  packing  and  shipping  of  tomatoes  should 
secure  Farmers'  Bulletin  1291  from  the  United  States  Department 
of  Agriculture,  Washington,  D.C. 

VARIETIES 

Selection  of  a  variety  adapted  to  the  purpose  and  the  location 
where  it  is  to  be  grown  is  the  first  step  in  the  production  of  a  good 
crop.  Unfortunately  some  lots  of  seed,  while  approximately  true 
to  name,  produce  fruit  of  poor  type.  It  is  high  time  that  all  growers 
of  tomatoes  should  begin  to  pay  close  attention  to  the  variety  used, 
and  to  the  source  and  quality  of  the  seed.  The  cost  of  the  seed  is 
an  insignificant  item  because  of  the  small  amounts  used.  One  pound 
is  sufficient  for  twenty-five  acres  in  most  of  the  ordinary  methods 
of  planting  in  California.  The  following  varieties  are  now  used 
extensively  for  the  various  purposes,  or  have  shown  promise  for 
use  in  the  state. 

Earliana. — This  is  the  earliest  maturing  variety.  It  is  character- 
ized by  small,  weak  vines  and  bears  medium  to  small  red  fruits 
that  tend  to  be  quite  flat  and  rough,  which  are  serious  defects.  Some 
strains  are  claimed  to  be  of  better  type  and  more  productive  than 


Circular  263]  TOMATO  PRODUCTION   IN   CALIFORNIA  13 

the  general  run  of  this  variety.  It  should  be  used  only  on  a  limited 
scale  for  extra  early  crop,  if  at  all. 

Bonny  Best. — This  variety  is  a  week  or  ten  days  later  than  Earli- 
ana.  It  produces  larger,  smoother,  rounder  fruits,  of  a  good  red 
color.  John  Baer  and  Chalk's  Jewel  are  varieties  that  are  identical 
with  Bonny  Best  when  good  strains  are  obtained. 

Livingston's  Globe. — This  variety  classes  as  a  second  early.  It 
has  medium  sized,  round,  pink  or  purple  fruits,  whch  are  firm  and 
stand  shipment  well.  It  is  used  very  extensively  for  shipping  pur- 
poses throughout  the  southern  states  and  in  Mexico,  but  does  not  seem 
to  be  used  much  in  California  as  yet. 

Stone. — This  is  a  late  variety,  having  vigorous  vines  and  large 
solid  red  fruits,  which  in  good  strains  are  smooth  and  nearly  round. 
This  variety  has  long  been  the  standard  for  canning  purposes  in 
eastern  regions,  and  is  used  for  that  purpose  in  California.  It  is 
also  the  sort  generally  grown  now  for  the  late  shipping  crop.  Stone 
or  Norton  appear  to  be  the  most  suitable  varieties  where  it  is  desired 
to  grow  a  "dual  purpose"  crop — that  is,  both  for  canning  and  for 
fall  shipment. 

Norton. — This  is  a  selection  from  Stone  developed  especially  for 
resistance  to  the  Fusarium  wilt,  which  is  a  valuable  characteristic 
in  many  parts  of  the  state  where  the  soils  are  infected  with  the  wilt 
disease.  Otherwise,  this  variety  is  identical  with  the  best-bred  strains 
of  Stone,  and  is  suited  to  the  same  season  and  uses.  Several  compe- 
tent observers  are  of  the  opinion  that  this  variety  will  be  of  great 
value  in  California,  as  it  was  grown  very  successfully  in  several 
places  in  1922. 

San  Jose  Canner. — This  variety  is  supposed  to  have  come  from 
Trophy,  a  very  old  variety.  It  has  very  large  rank  vines,  and  classes 
as  very  late  in  regard  to  maturity.  Most  of  the  common,  or  ' '  growers 
strains"  of  this  variety  produce  very  large,  rough,  flattened,  red 
fruits.  It  is  a  heavy  yielder  if  plants  are  started  early  enough  in 
the  season.  This  variety  is  not  suitable  for  shipment  but  is  used 
most  extensively  for  canning  purposes  in  central  and  northern  Calif- 
ornia.    A  few  growers  are  said  to  have  selected,  improved  strains. 

Morse's  San  Jose  Canner. — This  is  a  recently  introduced  and  much 
improved  strain  of  the  foregoing  variety,  having  deep,  smooth,  meaty 
fruits,  and  should  prove  desirable  for  canning  purposes. 

SEED  PRODUCTION 

Comparatively  few  tomato  growers  are  selecting  and  saving  seed 
for  their  own  use  at  the  present  time.     Where  one  is  engaged  in 


14  UNIVERSITY   OF   CALIFORNIA — EXPERIMENT   STATION 

tomato  production  over  a  period  of  years,  it  is  well  worth  while  for 
the  grower  to  select  and  save  sufficient  seed  for  his  own  use.  Im- 
proved, acclimated  strains,  the  result  of  careful  selection,  seem  to 
be  very  scarce  in  California.  Experiments  elsewhere  have  shown 
that  seed  selected  by  farmers  from  their  own  fields  out  yield  com- 
mercial seed  from  two  to  sixty  per  cent. 

Most  varieties  usually  contain  plants  varying  a  great  deal  in 
vigor  and  yield,  as  well  as  in  quality  and  type  of  fruit.  In  fact, 
it  seems  that  many  seed  stocks  are  actually  mixed,  containing  many 
plants  of  poor  type  or  low  yield.  The  procedure  recommended  is  to 
mark  certain  plants  that  show  vigor,  health  and  good  type,  about 
the  time  the  fruits  begin  to  ripen.  The  pickers  are  then  instructed 
to  take  no  fruit  from  the  marked  plants.  A  second  inspection,  two 
or  three  weeks  later,  will  then  enable  one  to  judge  of  the  productivity, 
quality  and  type  of  fruit.  Those  plants  which  seem  desirable  from 
this  standpoint  are  selected,  while  the  other  plants  marked  at  the 
first  selection  are  discarded.  It  is  best  to  save  separately,  and  to 
plant  one  row  in  the  field  the  next  year  with  seed  from  each  of 
the  selected  plants.  The  rest  of  the  seed  from  the  selected  plants 
can  be  mixed  and  used  for  the  main  planting.  From  the  best  row 
the  next  year,  seed  is  saved  in  sufficient  quantity  for  the  entire  plant- 
ing the  third  year.  Practically  all  of  the  benefit  derived  from 
selection  is  apparent  in  the  tomato  the  first  year  after  the  selection 
is  made.  Selection  simply  isolates  the  best  qualities  present  in  the 
original  variety,  and  the  improvement  over  the  average  is  usually 
sufficient  to  make  the  practice  quite  profitable.  However,  selection 
should  be  continued  from  year  to  year  to  eliminate  any  degenerate 
plants  and  to  preserve  and  improve,  if  possible,  the  qualities  of  the 
original  selection.  Indiscriminate  selection  of  good  fruits  without 
reference  to  the  vigor,  health,  yield  and  type  of  the  plant  from  which 
the  fruit  came  will  not  result  in  much  improvement,  for  even  poor 
plants  may  produce  a  few  good  fruits. 

Generally  speaking,  the  ideals  in  selecting  tomatoes  are:  First, 
a  vine  that  is  large,  vigorous,  free  from  all  disease,  and  producing 
a  large  yield  of  fruit;  second,  fruits  that  are  medium  to  large,  well 
colored,  smooth,  and  deep,  approaching  the  rounded  form  as  closely 
as  possible;  thirdly,  fruits  which,  when  cut  transversely,  show  well 
filled  cells  and  freedom  from  greenish  spots  and  hard  white  cores. 

Fruits  on  plants  from  which  seed  are  to  be  saved  should  be  allowed 
to  ripen  fully  on  the  vine.  When  large  quantities  are  to  be  saved 
from  a  number  of  plants,  the  ripe  fruit  should  be  gathered  at  inter- 


Circular  263] 


TOMATO  PRODUCTION    IN    CALIFORNIA 


15 


vals  and  dumped  into  wooden  barrels,  where  it  should  be  pounded 
into  a  pulp.  No  water  should  be  added — there  will  be  sufficient 
juice  in  the  pulped  fruits  to  insure  speedy  fermentation.  After 
standing  until  the  gelatinous  mass  surrounding  the  seed  is  well  de- 
composed, water  is  added.  Vigorous  stirring  facilitates  separation 
of  seed  from  pulp.  The  good  seed  sinks  to  the  bottom  while  the 
light  seed,  skins,  cores  and  pulp  rise  to  the  surface  where  they  can 
easily  be  removed.  Several  successive  washings  clean  the  seed  thor- 
oughly, after  which  they  should  be  removed,  spread  in  thin  layers  on 
wire  or  cloth  screens,  and  placed  in  the  sun  or  elsewhere  to  dry  as 
quickly  as  possible. 

In  cleaning  seed  on  a  larger  scale,  a 
flume  with  catch  basins  is  used  to  sepa- 
rate seed  from  pulp,  and  the  seed  is  dried 
in  rotating  cylinders  through  which  a 
current  of  hot  air  is  driven. 

CONTROL  OF  TOMATO  DISEASES 

Damping-off.  —  This  is  a  seed  bed 
trouble  which  attacks  tomatoes  and  all 
other  plants  grown  in  beds.  It  is  due  to 
several  kinds  of  fungi  which  are  often 
present  in  soils,  (fig.  4).  These  fungi 
attack  the  plants  at  the  surface  of  the 
soil,  causing  the  stem  to  shrivel  and 
turn  black,  while  the  top  soon  falls  over. 
This  disease  is  most  likely  to  do  serious 
damage  when  the  same  soil  is  used  year 
after  year  for  plant  beds.  It  is  also  likely 
to  spread  rapidly  when  the  surface  of 
the  soil  is  kept  damp  continually.  The 
control  consists  in  using  fresh  soil  in  the 
plant  beds  each  year;  watering  plants 
only  when  absolutely  necessary  and  then 
always  in  the  forenoon  so  that  plants  and 
soil  surface  may  dry  off  before  night; 
ventilating  the  plant  beds  as  freely  as  Fig.  4.-DamPing  off  of  to- 

possible  if  they  are  covered ;  and  avoiding     mato  seedlings.     This  disease 
,.  „      ,  ,  „  may  be  caused  by  several  fungi 

over-crowding  ot  plants  by  transplant-     which  are  particularly  liable  to 

ing  to  proper  distance  or  by  thinning.      become  active  when  there  is  an 
r     v  J  &        excess  of  moisture. 


16 


UNIVERSITY    OF    CALIFORNIA — EXPERIMENT    STATION 


Late-Blight. — This  disease  often  appears  in  coastal  districts  on 
potatoes  and  tomatoes.  It  spreads  only  in  moist  cool  weather.  In 
southern  California  the  late  fall  crop  is  sometimes  very  seriously 
injured  by  this  disease  when  the  fall  rains  come  earlier  than  usual. 
Due  to  its  irregular  appearance,  growers  are  seldom  prepared  to 
combat  it,  hence  serious  damage  results  occasionally.  The  effects  of 
the  disease  appear  soon  after  the  rains  commence  in  the  form  of 
numerous  black  spots  on  leaves  and  stems.     The  spots  enlarge  rapidly 


Fig.  5. — Leaves  of  plant  affected  by  "Western  Blight,"  showing  characteristic 
roll.     This  and  the  purple  color  of  the  veins  are  the  early  symptoms  of  the  disease. 


if  the  weather  remains  moist,  and  soon  the  whole  plant  blackens  and 
dies.  Fruits  in  all  stages  of  maturity  are  affected,  having  small 
dark  spots  which  enlarge  rapidly  and  soon  involve  the  decay  of  the 
whole  fruit. 

The  control  consists  in  spraying  the  plants  thoroughly  with  Bor- 
deaux mixture  whenever  early  rains  occur  and  the  disease  threatens. 
The  spray  material  is  prepared  by  dissolving  separately,  four  pounds 
of  Bluestone  and  four  pounds  of  unslaked  lime  (or  six  pounds  of 
hydrated  lime).  Each  solution  is  diluted  to  25  gallons  and  the  two 
are  then  poured  together,  making  50  gallons  of  the  spray  material. 
Where  no  special  spraying  machines  for  use  on  tomatoes  are  avail- 
able, power  orchard  sprayers  can  be  used  to  spray  the  tomato  fields. 


CIRCULAR  263]  TOMATO  PRODUCTION   IN   CALIFORNIA  17 

Fusariwn  Wilt. — This  disease  is  caused  by  a  fungus  living  in 
the  soil,  which  enters  the  plant  through  the  roots.  When  the  disease 
once  gets  into  a  field,  it  spreads  rapidly  in  succeeding  years.  The 
disease  is  said  to  occur  in  many  parts  of  the  state.  It  usually  appears 
a  few  weeks  after  the  beginning  of  hot  weather,  the  lower  leaves 
of  affected  plants  turn  yellow  and  dry  up  (fig.  5).  The  stems,  if 
split  open  reveal  dark  brown  streaks  in  the  woody  portion.  The 
disease  advances  rapidly  and  kills  the  entire  plant,  or  sometimes  only 
one  of  the  main  branches.  There  is  no  true  wilting  of  the  plant,  in 
the  ordinary  sense  of  the  word,  connected  with  this  disease.  The 
control  is  to  grow  resistant  varieties,  of  which  the  Norton  seems 
best  at  present,  though  Marvel,  an  early  variety,  and  Norduke,  a 
late  shipping  sort,  may  be  desirable  under  some  conditions.  These 
varieties  were  recently  developed  by  the  U.  S.  Department  of  Agri- 
culture. 

Summer  Blight  (Western  Blight). — This  trouble  occurs  very 
generally  in  the  state  and  is  known  by  several  names.  The  cause  is 
unknown.  The  disease  usually  appears  about  mid-summer  and  may 
gradually  involve  many  plants  during  the  season.  Affected  plants 
stop  growing,  the  margins  of  the  leaves  roll  upward,  and  the  under 
sides  become  purplish.  The  leaves  and  tips  of  the  stem  gradually 
dry  up,  and  eventually  the  whole  plant  dies.  No  satisfactory  control 
measure  can  yet  be  recommended. 

Root-Knot. — This  trouble  is  caused  by  nematodes — microscopic 
worms  which  infest  the  soil  and  which  enter  the  roots  of  tomatoes 
and  many  other  plants,  causing  the  characteristic  swelling  of  the 
roots.  Affected  plants  appear  stunted  and  yellowed,  and  die  slowly. 
The  trouble  can  always  be  recognized  by  pulling  up  the  plants  and 
inspecting  the  roots.  Extreme  caution  should  be  exercised  by  growers 
to  prevent  the  introduction  of  the  disease  on  vegetable  plants  or  seed 
potatoes  shipped  from  other  sections.  When  once  introduced  into 
the  soil,  nematodes  are  very  difficult  to  eradicate.  Flooding  the  land 
for  two  or  three  months,  thorough  drying  out  of  the  soil  over  summer, 
summer  fallow,  and  growing  resistant  crops  for  two  years  are  prac- 
tices that  have  been  recommended.  The  small  grains,  the  Iron  variety 
of  cowpea,  and  the  velvet  bean  are  some  of  the  crops  resistant  to 
nematodes.  One  should  always  be  sure  that  the  soil  used  for  plant 
beds  is  free  from  nematodes,  for  infected  beds  are  often  responsible 
for  infecting  a  field  and  spreading  the  trouble. 

Fruit  Spot  (Anthracnose) . — This  is  caused  by  a  fungus  which 
attacks  the  fruit  in  damp  weather  in  the  fall.  Sometimes  the  black 
circular  spots  of  decay  are  noticeable  when  the  fruit  is  picked,  and 


18  UNIVERSITY    OP    CALIFORNIA EXPERIMENT    STATION 

such  fruit  should  of  course  be  destroyed.  The  more  serious  damage 
caused  by  this  disease,  however,  is  the  decay  of  fruit  during  shipment 
or  after  reaching  market.  There  was  some  complaint  of  this  the 
fall  of  1922.  It  is  believed  that  spraying  the  plants  with  standard 
Bordeaux  mixture  will  control  the  disease,  if  applied  just  before 
the  fruit  begins  to  ripen.  Spraying  of  course  entails  the  additional 
task  of  wiping  the  fruit  as  it  is  packed.  Infected  fruit  should  be 
destroyed.     Seed  disinfection  may  aid  in  preventing  the  trouble. 

Mosaic. — This  disease  causes  a  mottled  appearance  of  the  leaves; 
the  plants  are  stunted  and  usually  die  without  producing  much  fruit. 
The  disease  is  readily  spread  in  the  field  by  insects  and  other  means. 


Fig.  6. — Tomatoes  showing  blossom  end  rot.  The  cause  of  this  disease 
is  somewhat  obscure,  but  thus  far  remedial  measures  consist  in  giving  good 
care  and  not  allowing  the  plants  to  surfer  for  lack  of  water. 

It  has  been  recently  reported  as  doing  considerable  damage  in  some 
places.  Infected  plants  should  be  promptly  pulled  up  and  burned 
or  buried.  Probably  the  most  important .  step  in  controlling  the 
disease  is  to  destroy  the  perennial  weeds  related  to  tomatoes,  on 
which  the  disease  over-winters.  Horse-nettles,  ground  cherries  and 
matrimony  vine  especially  should  be  eliminted  from  the  neigh- 
borhood of  the  plant  beds  and  from  the  field  as  well,  if  possible. 
Tomatoes  should  not  be  grown  after  potatoes,  for  the  volunteer  potato 
plants  which  usually  are  quite  numerous  the  year  after  potatoes 
are  grown,  would  be  a  source  of  Mosaic  infection  to  the  tomato  plants. 
Blossom  End  Rot. — This  is  a  common  disease  in  most  parts  of 
the  state,  though  the  damage  done  varies  much  according  to  the  season. 
The  first  stage  occurs  on  either  green  or  ripening  fruits,  as  an  irregu- 
lar brownish  patch  at  the  blossom  end  of  the  fruit.  If  the  trouble 
does  not  develop  beyond  this  stage,  as  is  sometimes  the  case,  little 
harm  is  done.     But  generally  the  disease  advances  rapidly,  develop- 


Circular  263]  TOMATO  PRODUCTION   IN   CALIFORNIA  19 

ing  a  black  dry  leathery  rot  which  may  advance  until  the  lower 
half  of  the  fruit  is  decayed.  The  disease  is  usually  associated  with 
drought  conditions,  where  the  plants  are  not  able,  on  account  of  dry 
soil  or  limited  root  system,  to  take  up  moisture  as  fast  as  it  is  needed. 
The  disease  also  occurs  where  plants  have  made  excessively  rank 
growth  of  vines  early  in  the  season,  and  are  then  checked  by  insuffi- 
cient moisture  when  the  fruit  is  ripening.  The  prevention  of  this 
disease  seems  to  lie  in  proper  regulation  of  the  moisture  supply 
(fig.  6).  Everything  done  to  encourage  development  of  a  deep  root 
system  by  the  plant  will  also  aid  in  preventing  disease.  Also,  the 
selection  of  seed  from  plants  bearing  fruits  not  affected  by  the  disease 
offers  much  hope  for  its  control  in  succeeding  years. 

Failure  to  set  fruit. — This  is  a  frequent  cause  of  trouble,  especi- 
ally at  certain  seasons  of  the  year.  Although  the  plants  may  bloom 
profusely  many  flowers  may  fall  without  setting  fruit.  One  fre- 
quent cause  of  the  trouble  lies  in  the  excessively  rank  vegetative 
growth  of  the  plant,  which  is  likely  to  occur  when  the  water  supply 
is  too  liberal  or  when  the  soil  is  excessively  rich  in  nitrogenous  matter. 
Another  cause  is  the  very  low  humidity  of  the  air  which  often  occurs 
in  summer.  This  condition,  in  connection  with  high  temperature 
and  high  winds,  may  cause  most  of  the  blossoms  to  fall. 

Avoiding  too  much  nitrogenous  fertilizer  and  irrigating  sparingly 
if  at  all  during  the  first  bloom  stage,  will  promote  a  better  set  of 
fruits.  Windbreaks  and  the  selection  of  a  type  of  plant  having 
heavy  foliage  will  be  helpful  in  other  cases. 

For  aid  in  preparing  this  circular,  the  writer  is  indebted  to 
R.  G.  Risser  of  the  California  Vegetable  Union;  F.  A.  Dixon  of  the 
Canners  League;  S.  W.  Cunningham  of  the  southern  California 
Canners  Bureau;  and  R.  E.  Smith,  Plant  Pathologist  in  the  College 
of  Agriculture. 


